Doppler diagnosis of intracranial artery occlusive disorders

Area of Science:

• Neurosonology
• Cerebrovascular Medicine
• Medical Imaging

Background:

• Occlusive disease of major intracranial arteries poses a significant risk for stroke.
• Accurate assessment of intracranial arterial stenosis is crucial for patient management.
• Non-invasive methods for evaluating cerebral blood flow are highly desirable.

Purpose of the Study:

• To evaluate the utility of 2 MHz pulsed wave Doppler ultrasound for assessing blood flow velocity in patients with intracranial arterial occlusive disease.
• To determine the relationship between measured blood flow velocities and the degree of arterial stenosis.

Main Methods:

• Utilized pulsed wave 2 MHz Doppler with acoustical focusing to record blood flow velocity through the intact cranium.
• Included 11 patients diagnosed with occlusive disease of major intracranial arteries.
• Correlated Doppler-derived flow velocities with angiographically determined residual lumen diameter.

Main Results:

• Elevated blood flow velocities were consistently detected at stenotic segments, including the carotid siphon, middle cerebral, anterior cerebral, and basilar arteries.
• A strong inverse correlation (Kendall's Tau = -0.89, p = 0.0001) was observed between residual lumen diameter and flow velocity, indicating higher velocities with greater stenosis.
• The technique provided reliable blood flow velocity measurements through the intact skull.

Conclusions:

• Transcranial Doppler (TCD) ultrasound is a valuable non-invasive tool for evaluating the severity of stenotic lesions in major intracranial arteries.
• TCD findings correlate significantly with angiographic evidence of arterial narrowing.
• This method aids in the diagnostic workup and management of patients with cerebrovascular occlusive disease.